Brooding means thinking deeply about something in a dark, worried, or moody way. When you're brooding, you're dwelling on problems, disappointments, or troubling thoughts that circle around in your mind like storm clouds, unable to let them go. A student might sit brooding over a mistake they made, replaying it over and over instead of moving forward.

The word captures a specific quality of thought: heavy, gloomy, and inward-focused. Someone who is brooding often stares off into space with a serious or troubled expression, lost in their own thoughts. You might notice a friend brooding in the corner during recess, thinking about an argument instead of playing.

Brooding can also describe an atmosphere or mood. A brooding sky looks dark and threatening before a storm. A brooding castle in a story feels heavy with secrets and shadows.

The word comes from birds sitting on eggs to hatch them, which requires long periods of still, focused waiting. That sense of sitting with something for a long time carried over into our emotional use of the word. While thinking carefully about problems can be useful, brooding usually means getting stuck in negative thoughts rather than working toward solutions.